Bob Antonius’ 7-year-old daughter and 11-year-old son never used to sit down and play together. But that changed when his children discovered the Rainbow Loom, a crafts kit used to weave rubber bands into colorful bracelets.

“I joke that we weren’t truly a family until the Rainbow Loom,” Antonius, the manager at the Michaels arts and craft store in Braintree, said Sunday. “It’s something everyone can enjoy, even adults.”

Stores on the South Shore and beyond are struggling to keep the Rainbow Loom – and others of its ilk – on their shelves, as boys and girls are sporting the fad bracelets, made by looping colorful bands together into Brunnian links using a plastic loom. The demand is similar to past toy trends such as Beanie Babies, Webkinz, Tickle Me Elmo or Cabbage Patch Kids.

Michaels has an exclusive, one-year contract to sell Rainbow Loom, and Antonius said the craze is one employees are not used to seeing.

“Usually there are big Christmas craft items, but nothing even remotely close to this kind of demand,” said Antonius. “The Rainbow Looms knocks it out of the park.”

Michaels in Braintree had several dozen Rainbow Looms in stock at the store’s entrance Sunday. One shopper immediately grabbed four kits, which sell for $16.99 each. Crafts retailer A.C. Moore sells the similar Cra-Z-Loom, which was has been sold out at the Hanover location.

Antonius said the greeting on his store’s phone recording says whether Rainbow Looms are in stock, otherwise employees would be bombarded with inquiries.

Invented by Cheong Choon Ng, a Malaysian immigrant from Michigan, the Rainbow Loom comes with two plastic template boards, a hook, 24 plastic clips and 600 bands. Refills of elastics and clips are sold separately. And, those are just as hard to find as the looms. A.C. Moore in Hanover only had bags of pink and yellow rubber bands left on Sunday. Across the street, the Michael’s store on Route 53 was sold out of the rubber bands, but flush with a fresh stock of looms.

While Ng created the Rainbow Loom in 2010, the kit’s popularity soared within the last year, especially since its recent retail debut at Michaels.

“All it takes is one kid bringing it to school, and then 25 kids in their class get it, and then the whole grade gets it, and then the whole school,” Antonius said. “I’ve had people waiting outside the store for the delivery to come off the truck.”

Other manufacturers are cashing in on the demand for Rainbow Loom, including the makers of the FunLoom, which was sold out Sunday at The Toy Box in Hanover.

Employee Erin Hellmuth said the store sold 90 FunLooms last Wednesday alone, and yields at least five calls a day from parents looking to get their hands on one.

Page 2 of 2 - “I wish I thought of the idea,” said Hellmuth, who wore a multi-colored bracelet her son made. “It’s fun, and I think parents like it, too.”

Speculating over the reason for the loom’s popularity, Hellmuth said they allow children to be creative and unique in the patterns and colors they choose, and are affordable for most families.

Ariane Foster, another Toy Box employee, said the looms bring youngsters together, rather than divide them.

“All types of kids can do it. It’s an ice breaker and something to talk about,” she said.

Amy Wojdag and her 7-year-old daughter, Emma, stopped in the store Sunday to purchase more rubber bands and fasteners.

“I ran out of C-clips already. You use them to put the elastics together,” Emma Wojdag said.

“It’s amazing,” Amy Wojdag added. “I thought it would be difficult for her to do, but it’s not at all.”

Tracy Sheehan of Marshfield said her daughters, Siena 9, and Ruby, 7, wear their bracelets to school everyday. “They have from like three to 10 on their arms,” Sheehan said.

The girls also make bracelets for their friends. “They’ve been taking orders,” Sheehan said. “It’s a fun activity and they’re not playing video games or on the iPad.”